/*
 * Licensed to Elasticsearch B.V. under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch B.V. licenses this file to you under
 * the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package co.elastic.apm.agent.log.shipper;

public interface FileChangeListener {

    /**
     * Retried until success. Implementations are responsible for doing a backoff.
     *
     * @param file
     * @param line
     * @param offset
     * @param length
     * @param eol
     * @return
     * @throws Exception If there is an exception while processing the line.
     *                   Throwing an exception stops tailing the file.
     */
    boolean onLineAvailable(TailableFile file, byte[] line, int offset, int length, boolean eol) throws Exception;

    void onIdle();

    /**
     * May be called from a different thread than the one owned by {@link FileTailer}
     */
    void onShutdownInitiated();

    void onShutdownComplete();
}
